The invention pertains to a liquid ring vacuum pump, in general, and to an arrangement to minimize the cooling liquid consumption as well as to prevent cavitation in a liquid ring vacuum pump, in particular.
The suction capability of a liquid ring vacuum pump depends on the operating liquid. Where water is used as the operating liquid the suction capability of the water ring-vacuum-pump can be considerably influenced by adjusting the temperature of the operating liquid. In particular, for higher vacuums a lower operating liquid temperature results in better operation. Therefore, cooling the circulating operating liquid is necessary. Normally when water is used as operating liquid cooling is achieved by removing a part of the heated liquid from the operating liquid circuit and by replacing that amount with cool, fresh liquid from a supply line. Therefore the operation of a water ring-vacuum pump usually requires considerable fresh water consumption, which affects the operating costs of such a pump.